As gay rights issues gather momentum, major religious groups are being forced to confront where they stand on the sensitive topics of same-sex unions and clergy - and are often taking widely varied approaches.

For some, homosexuality has become the most divisive issue since the ordination of women, and has threatened to split denominations in two.

With US and Canadian courts in the process of redefining homosexual rights, possibly to include marriage, churches now face not only what it means to include gay and lesbian believers as full participants but also how to respond to the potential redefinition of an institution most consider the bedrock of society.

Many have backed the passage, in 37 states and Congress, of "defense of marriage" acts, which define marriage as applying only to a man and a woman; but some clergy support the bid for equal marriage rights.

President Bush spoke out against same-sex marriage on Wednesday, saying further legal action might be needed beyond the defense acts, implying he might support a constitutional amendment.

The acts could eventually be challenged on the basis of the recent US Supreme Court decision upholding certain gay rights. The top court in Massachusetts will soon decide if prohibiting gay marriage is contrary to the state constitution. It would make it the first high court in the US to do so.

"What happens in the public realm has an impact, but faith communities make distinctions between what they believe faith demands and what the law permits," says James Childs, head of a task force on sexuality at Evangelical Lutheran Church in America (ELCA).

While mainline churches have long been debating the topics of ordinations and same-sex unions, they're now taking on new urgency. The tension over the issue will be on display over the next week in Minneapolis, where the Episcopalians must take a stand on last month's election of an openly gay man as the next bishop of New Hampshire. They're also debating whether to create a rite of blessing for unions. Lutherans, Methodists, and Presbyterians are in the throes of discussion on similar issues.

Tougher stance

Other churches are taking harder lines. The Vatican's decision Thursday to launch a global campaign against same-sex marriage included guidelines for politicians and lay people - non-Catholics included - on how to affect public opinion and legislative action. The Southern Baptist Convention (SBC) in June adopted a resolution "to oppose steadfastly" all efforts to validate same-sex unions.

"The church should set out a moral vision of what we believe God has laid down as the ground rules for human society; we believe the family is a divine institution and society ought to acknowledge its special status," says Dr. Richard Land, an SBC leader. A federal constitutional amendment is needed, he says, to prevent "judicial elites from foisting their value system on the nation."

Churches support basic rights and civil liberties for homosexuals and condemn violence and discrimination against them, but traditional Christian doctrine has termed homosexual practice incompatible with scripture.

The divide within churches is between conservatives, who feel the authority of the Bible is at stake, and liberals, who say scriptural references are misunderstood and that gays and lesbians deserve full participation as children of God. Some say Bible passages on homosexuality don't address the question of people in faithful, lifelong relationships.

"With the pace of change in society, more and more people are coming forward asking about unions, seeking the blessing of their church," says Sue Laurie of Reconciling Ministries Network, which advocates more inclusion in the United Methodist Church.

Methodist policies prohibit unions and ordination, and in 2000 the denomination voted against change. "The policies we have now were just put in place in 1996, and are a backlash to the culture moving ahead," Ms. Laurie says. Her group seeks to modify the language of "incompatibility" to win acknowledgment that differing views exist among Methodists of good faith.

Lutherans have a tradition but no explicit policies on unions or ordination, says Dr. Childs. To avoid a divisive battle, the ELCA began a four-year effort to engage congregations in discussions, reviewing biblical and church teachings, scientific research, the ways people make ethical choices, and the impact of decisions on the church's mission.

A task force prepared study materials and will report findings and recommendations in 2005. The shift in the culture will play out in the discussions, he says. "There may be a need to recognize the reality and legitimacy of same-sex companionships without making it the equivalent of marriage, to guard the priority of heterosexuality in the biblical account of creation."

At the same time, ELCA's National Lutheran Youth Organization has just adopted a resolution in support of same-sex unions and gay ordination.

The Presbyterian Church (USA) has taken a slightly bolder stance. While rejecting gay ordination, it voted to allow "holy unions" as long as they differed from weddings. Unions are being performed. But in at least one church, Calvary Presbyterian in San Francisco, the Rev. Laird Stuart says no one has yet requested a ceremony. When he asked a gay member in a long-term relationship about it, the man said: "We know the controversy it would cause and we don't want that, but in our hearts we are married."

A few pastors, however, are taking a stand beyond denominational strictures. In June, a Presbyterian minister in Cincinnati was defrocked for performing a same-sex marriage ceremony. The Rev. Stephen Van Kuiken said he acted on the "desire to be open and honest. We cannot hide the fact that when we do same-sex ceremonies, all the parties involved ... understand that we are celebrating Christian marriage."

This is part of the dilemma facing churches, courts, and legislatures as they try to sort out the legal and desirable forms domestic partnerships should take in the 21st century.

A Pew Research Center poll of Americans released last week shows that the opposition to gay marriage dropped over the past seven years from 65 percent to 53 percent. All religious groups except evangelicals showed a steep decline. Other surveys, however, have shown a slight upturn in opposition to gay marriages since the Supreme Court decision.

Fundamental divide

It's clear that both sides see this issue as something well worth fighting for - equal rights vs. a 2,000-year-plus tradition with biblical meaning and societal import. It's a battle likely to play out over many years.

In Canada, courts which recently termed the prohibition of gay marriage unconstitutional also said the country should properly deal with the issue through legislation. Some Americans, too, worry about the consequences of change through judicial decisionmaking.

"When there isn't ample democratic ventilation, there's a danger of precipitous backlash," says John Witte Jr., an expert on law, religion, and marriage at Emory University in Atlanta. "Some would argue that's one reason for the continued cultural fallout over Roe v. Wade. I fear something akin to that might occur as a reaction ... in dealing with same-sex unions and marriages."

If the changes come about by statute, then it would be a matter for the civil realm, and religious bodies would be free to opt out, he says. But if it becomes a constitutional question, then it's much more likely churches who refused to perform marriages could be seen as discriminatory.

"In some sense, what is eventually going to emerge is a collision between religious liberty and sexual liberty," he says.